Place the points on the grid. Draw one smooth curve through all of them. Carry the line on so that it crosses the y-axis.
What is the pH of $25.0\,\text{cm}^3$ of $1.00\,\text{mol dm}^{-3}$ sodium hydroxide?
What is the pH of the solution after $15.0\,\text{cm}^3$ of acid has been added?
Use your graph to estimate the pH of the solution at the end-point.
Using your result from (i) and your graph, what volume of acid is needed to neutralise $25.0\,\text{cm}^3$ of $1.00\,\text{mol dm}^{-3}$ sodium hydroxide?
Use the equation below together with your answer to (c)(ii) to calculate the concentration of sulfuric acid used in the experiment. $\text{H}_2\text{SO}_4 + 2\text{NaOH} \rightarrow \text{Na}_2\text{SO}_4 + 2\text{H}_2\text{O}$
Describe how a student obtains pure, dry crystals from aqueous sodium sulfate.